anaemia tutorial Flashcards
Haemolysis definition vs haemolytic anaemia
haemolysis=increased destruction of red blood cells
(reduced red cell survival)
haemolytic anaemia=increased destruction, decrease Hb->
shortened RBC survival->
anaemia
how to treat haemolytic anaemia
Folic acid (because of the increased requirement for
erythropoiesis)
- Splenectomy (if severe) to increase red cell life span
difference between conjugated and unconjugated bilirubin
-soluble? excreted in urine? what hepatic jaundice? causes?
conjugated
-water soluble
-can be excreted in urine (dark urine)
-accumulates in post-hepatic jaundice
-causes include cholecystitis
unconjugated
-insoluble in blood
-cannot be excreted in urine
-accumulates in pre-hepatic jaundice
-causes include haemolysis
what is a direct antiglobulin test
-test to detect presence of ab bound to RBC surface.
-ie. with rabbit ab to human immunoglobulin
-pts with autoantibodies: ab bind to antigen on erythrocyte membrane
what does it suggest if DAT is positive (direct antiglobulin test)- and what is it
anti-immune haemolytic anaemia (AIHA)
WHAT:
-associated with SLE/underlying lymphoid cancer (lymphoma)
examples of environmental factors which can damage RBC- non-immune vs immune mediated (DAT +ve)
non-immune
-malaria, snake venom
immune
-auto-immune
inherited defects and conditions associated with it- abnormal red cell membrane
hereditary spherocytosis
inherited defects and conditions associated with it- abnormal Hb
sick cell anaemia
inherited defects and conditions associated with it- defect in glycolytic pathway
pyruvate kinase deficiency
inherited defects and conditions associated with it- defect in enzyme of pentose shunt
G6PD deficiency- > dysregulation of glutathione metabolism means Red cells are more vulnerable to oxidant damage
what does it mean if you can see irregular contracted cells and heinz bodies
and what to avoid if you have this condition
oxidant damage to RBC
-AVOID axidant drugs - don’t eat broad beas
difference between intravascular haemolysis and extravascular haemolysis
- Intravascular haemolysis=acute
damage to the red cell - Extravascular haemolysis= when defective red
cells are removed by the spleen
treatment of iron deficiency anaemia
iron replacement therapy
ie. Ferrous sulphate tablets
List symptoms and signs of iron deficiency anaemia
Diet – vegetarian/vegan
Gastrointestinal symptoms: dysphagia/abdominal pain, haematemesis/rectal bleeding
Menstrual history/post-menopausal bleeding
Weight loss
Medication – e.g. aspirin/NSAIDs
clinical signs of iron deficiency anaemia
-koilonychia-centre of nail depressed.
-glossitis
-angular stomatitis- skin irritation on corner of mouth
what is hepcidin and when is it secreted
-secreted by liver in response to high iron stores
-hepcidin increased in inflammatory states—> reducing iron supply
what is anaemia of chronic disease
Anaemia in patients who are unwell
- bleeding? NO
- reduced red cell survival (haemolysis)? NO
- marrow infiltrated? NO
- iron/B12/ folate deficient? NO
common causes of anaemia of chronic disease and treatment
- Infections such as TB and HIV
- Rheumatoid arthritis and other autoimmune disorders
- Malignancy
treat underlying cause
difference between vit B12 and folic acid- what they are required for
Vitamin B12 is required for
1. DNA synthesis
2. Integrity of the nervous system
Folic acid is required for
1. DNA Synthesis
2. Homocysteine metabolism
causes of vitB12 deficiency and treatment
1) Inadequate diet,
veganism// Oral supplements
2) Gastrectomy or Autoimmune: Pernicious
anaemia (anti GPC
and IF antibodies) //
treat: Hydroxocobalamin
injections (IM)
3) Terminal ileum
* Crohn’s disease or Ileal resection
treat: Hydroxocobalamin
injections (IM)
folic acid cause of reduced availability and treatment
diet- poverty/alcohol
malabsorption - disease/resection
treat: oral supplement
folic acid and what increases demand– plus treatment
pregnancy
lactation
increase cell turnover - haemolysis
oral supplement
microcyte, normocyte, macrocyte- which one is hypochromic, which normochromic
Microcytic – usually also hypochromic
Normocytic – usually also normochromic
Macrocytic – usually also normochromic
Inherited defect leading to reduced synthesis of
globin:
THALASSAEMIA
what is thalassaemia a vs thalassaemia b
a-defect in a chain synthesis
b-defect in b chain synthesis
difference between anaemia of chronic disease and iron deficiency anaemia
anaemia of chronic disease- Ferritin high
iron deficiency anaemia- ferritin low
normocytic anaemia causes
-recent blood loss
-failure of production of red cells
-pooling of red cells in spleen (hypersplenism/liver cirrhosis)
